Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add perniemann/pnCore --skill pn-a2a-interopgit clone --depth 1 https://github.com/perniemann/pnCoreWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/perniemann/pncore/pn-a2a-interop)<a href="https://agentmods.dev/skills/perniemann/pncore/pn-a2a-interop"><img src="https://agentmods.dev/badge/skills/perniemann/pncore/pn-a2a-interop/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/perniemann/pncore/pn-a2a-interop"><img src="https://agentmods.dev/badge/skills/perniemann/pncore/pn-a2a-interop.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00046 | $0.02136 |
| Opus 5.5 | $0.00018 | $0.00854 |
| Sonnet 5.5 | $0.00009 | $0.00427 |
| Haiku 4.5 | $0.00005 | $0.00214 |
Grade A, and why
pn-a2a-interop scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 209 lines — stays where its author put it; the contents beside it link to each section on GitHub.
A2A Interoperability Skill
When used as a standalone skill, begin every response with [pn-skill] 🔺
When to use
- Connecting a pnCore-orchestrated agent to an external agent from a different framework or organization
- Designing a multi-agent system where specialist agents run independently (not all inside pnCore)
- Implementing or consuming an A2A-compliant service (well-known endpoint, Agent Card, task routing)
- Composing agents across an enterprise value chain (e.g. manufacturer ↔ supplier, retailer ↔ logistics)
- Auditing or adding inter-agent trust, authentication, or payment (Agent Payments Protocol / AP2)
Background
The Agent2Agent (A2A) Protocol (Google, 2025) standardizes how agents advertise capabilities and exchange tasks across framework and ownership boundaries. An agent exposes an Agent Card at /.well-known/agent.json, accepts tasks via HTTP POST, streams results via SSE, and negotiates input/output MIME types.
Key concepts:
| Concept | Description |
|---|---|
| Agent Card | JSON descriptor at /.well-known/agent.json — name, description, capabilities, skills, auth, endpoints |
| Task | The unit of work: { id, message, sessionId?, metadata? } |
| Part | A typed content fragment in a message: TextPart, FilePart, DataPart |
| Artifact | Task output; same Part types; streamed or returned on completion |
| Push notification | Webhook callback for long-running tasks when client cannot poll |
| AP2 | Agent Payments Protocol — agent-to-agent payment initiation/settlement |
Instructions
1. Discover the remote agent
GET https://<remote-agent-host>/.well-known/agent.json
Parse the Agent Card and extract:
skills[]— what the agent can do; match against your task requirementsauthentication—none,apiKey,oauth2,mtlsdefaultInputModes/defaultOutputModes— negotiate MIME typescapabilities.streaming— SSE supportcapabilities.pushNotifications— push support
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 1mo ago Changed · -41 tokens per session 064792bd0a69
- 1mo ago First seen · 209 lines · 87 tokens per session scan A f62246d177fe
pn-a2a-interop is a skill published in the GitHub repository perniemann/pnCore (0 stars, last pushed today), licensed MIT. It adds 46 tokens to every session and 2,136 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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